A technique is known in the known art in which when inverting the polarity of a data signal in a liquid crystal display device, a plurality of data lines are short-circuited in synchronism with the polarity inversion timing to thereby save the power consumption (e.g., Patent Document 1). Also known is a technique directed to a configuration where the data signal is output from a data driver, wherein the polarity of the data signal is controlled by inputting a polarity-specifying signal to the data driver (e.g., Patent Document 2).
Also known in the art is charge-shared impulse in which a voltage corresponding to black display is realized by utilizing an operation of short-circuiting a plurality of data lines (e.g., Patent Document 3). Specifically, a scan signal line is selected at least in one effective scanning period in each frame period, and at least one black signal insertion period is provided after the scan signal line is selected in the effective scanning period and before the scan signal line is selected in an effective scanning period in the next frame period. Then, in the black signal insertion period, the scan signal line is selected and data signal lines are short-circuited. As a result, the charges of the data signal lines selected in the black signal insertion period are averaged out, and the display is brought closer to black. Therefore, the display of picture elements can be made substantially black within one frame period by repeated selection in the black signal insertion periods.
On the other hand, another driving technique is also known in the art in which during a write period of a data signal to a picture element forming portion connected to a plurality of adjacent scan lines, the polarity of the data signal is maintained, and the polarity is inverted for each frame (Patent Document 4). The driving technique (hereinafter referred to also as a “multiple line inversion driving operation”) has a lower polarity transition frequency as compared with a driving operation in which the polarity of the data signal is transitioned for each scan line and the polarity is inverted for each frame. Therefore, it is possible to save the power consumption.
Citation List
Patent Document
Patent Document 1: Japanese Published Patent Application No. 9-243998
Patent Document 2: Japanese Published Patent Application No. 2002-196731
Patent Document 3: International Publication WO2007/015347 pamphlet
Patent Document 4: Japanese Published Patent Application No. 9-15560